Applications of valves in high-performance fluidics control often require quick response time, small size, long life, and operation under a wide range of fluid flows; often, valves meeting these criteria are required to provide hundred micron throws with several grams of force while closed.
Magnetically-actuated valves are one class of valves which can satisfy these criteria, and an example of such a valve is provided by U.S. Pat. No. 5,085,402. While these magnetically-actuated valves are useful for their intended purposes, one limiting factor in their application is their generally high cost. This high cost may unacceptably drive up cost of a final product, especially in the case of consumer products, where price can critically govern sales.
There are other classes of valves which potentially can provide throws having sufficient force (e.g., piezoelectric valves), but these valves generally are too large and expensive when constructed to meet the criteria mentioned above. Furthermore, piezoelectric valves often require a large driving voltage, which can unacceptably increase power supply requirements.
A need exists for a magnetically-actuated valve that is relatively inexpensive to produce. Ideally, such a valve should be extremely reliable, providing millions of cycles of repetition during the valve's lifetime. Such a valve should provide strong throws with response time on the order of milliseconds or better. Finally, such a valve should ideally be small. The present invention satisfies these needs and provides further, related advantages.